Originally Posted by WMichaels
As best I can tell. I think our torque converters have aroung a 2,400 - 2,600 rpm stall.
For those who may not know... The "stall" rating is the point at which the converter locks up like a fully engaged clutch.
This happens in each gear. Since the shift points are above 2,600 rpm at WOT (it enters the next higher gear above the stall point) the converter stays locked up as it goes through the gears as long as your foot is burried in the throttle.
...Which is determined by observing maximum RPMs while keeping the car stationary using the brakes under full throttle acceleration.
But even then there is still slippage since it is a hydrodynamic interaction. Unless in a mechanical lock-up mode there will always be a small slip percentage. I've learned that Mercedes (at least some of the newer models) have a really advanced lock-up converter that works in all forward gears. Anyone know if the Crossfire has that feature? Or does ours only work in top gear (like most other vehicles with a lock-up feature)? This increased efficiency must be why the auto gets slightly better mpg than the manual. Anyway, interesting topic.
You guys got me thinking too much. :?: :idea: